principles of inheritance

Question 1

characters inherited by offsprings from parents is called……

Answer 1

inheritance

Question 2

differences between progeny and parents is called

Answer 2

variation

Question 3

who were the 3 scientists that rediscovered Mendel’s work

Answer 3

de vrie
Correns
tschermak

Question 4

specific physical location of a gene or other DNA sequence on a chromosome

Answer 4

locus

Question 5

basic physical and functional unit of heredity

Answer 5

gene

Question 6

slightly variable forms of a gene

Answer 6

allele

Question 7

physical traits

Answer 7

phenotype

Question 8

genetic makeup

Answer 8

genotype

Question 9

traits studied by mendel

Answer 9

G for green fruit color.. 
R for round seed shape.. 
A for axial flower position
V for violet flower color.. 
I for inflated pod shape.. 
T for tall plant height.. 
Y for yellow seed color..

Question 10

state first law of inheritance/ law of dominance

Answer 10

characters are controlled by factors/ genes
factors occur in pair
incase of dissimilar factors, one factor dominates the other

Question 11

what is test cross

Answer 11

mating w recessive parent to determine the genetic makeup

Question 12

when dominant allele does not express the dominant characters fully in heterozygous condition

Answer 12

incomplete dominance

it is an exception to Mendel’s 1st law

Question 13

when both alleles express themselves fully

Answer 13

codominance

eg- human blood grp

Question 14

more than 2 alleles of a gene in a population

Answer 14

multiple alleles

Question 15

state second law of inheritance/ law of segregation/ law of purity of gametes

Answer 15

during gamete formation the 2 alleles of a gene must segregate to move into different gametes

Question 16

state third law of inheritance/ law of assortment

Answer 16

alleles of genes located on different chromosomes assort independently of each other

Question 17

what is linkage (exception of third law)

Answer 17

when 2 genes are situated on same chromosome and they are situated closely to each other then both the alleles on one chromosome are passed together in the gamete

Question 18

linkage is inversely proportional to

Answer 18

distance between genes

Question 19

which insect did T.H. Morgan choose

Answer 19

drosophila melanogaster (fruit fly)

Question 20

reasons for which th morgan chose drosophila melanogaster

Answer 20

has contrasting traits
2 week lifecycle
grows easily in lab
male and female are morphologically distinct

Question 21

change in quality or quantity of genetic material

Answer 21

mutation

Question 22

anything which causes mutation

Answer 22

mutagens (physical/ chemical)

Question 23

types of mutation

Answer 23

genomatic- number
chromosomal- structure
gene

Question 24

types of genomatic mutation

Answer 24

polyploidy- repetition of haploid set

aneuploidy- loss or gain of 1 or few chromosomes

Question 25

what does colchicine do

Answer 25

stops the formation of spindle fibers in metaphase

Question 26

types of aneuploidy

Answer 26

monosomic- turner syndrome (-1)
nullisomic (-2)
trisomic- down syndrome (+1)
tetrasomic (+2)

Question 27

types of chromosomal mutation

Answer 27

intrachromosomal

interchromosomal

Question 28

types of intrachromosomal mutation

Answer 28

deficiency- loss of terminal part
deletion- loss of mid part
inversion-

Question 29

types of interchromosomal mutation

Answer 29

insertion

translocation

Question 30

types of gene mutation

Answer 30

point

frameshift

Question 31

types of point mutation

Answer 31

transversion- purine is replaced by pyridine or vice versa

transition- when purine is replaced by purine…..

Question 32

sickle cell anemia is caused by

Answer 32

point mutation (transversion)

Question 33

types of male and female heterogamety

Answer 33

MALE-
xo type (insects)
xx-xy type (humans, drosophilla)
FEMALE-
zz-zw type

Question 34

what is parthenogenesis

Answer 34

a form of reproduction in which an egg can develop into an embryo without being fertilized by a sperm
male- arrhenotoky (honeybees)
female- thelytoky

Question 35

types of genetic disorder

Answer 35

mendelian- caused due to mutation of a single gene

chromosomal- caused due to absence or excess of abnormal chromosomes

Question 36

types of mendelian disorders

Answer 36

autosomal

sex linked

Question 37

list 2 x linked disorders

Answer 37

color blindness

hemophilia

Question 38

what type of disorder is sickle cell anemia

Answer 38

autosomal

Question 39

an inherited disorder that increases the levels of a substance called phenylalanine in the blood

Answer 39

phenylketonuria

Question 40

2 types of thalassemia

Answer 40

α thalassemia (ch16)

β thalassemia (ch11)

Question 41

list recessive autosomal disorders

Answer 41

sickle cell anemia
phenylketonuria
thalassemia
cystic fibrosis

Question 42

what happens in cystic fibrosis

Answer 42

excess mucus produced

Question 43

name a dominant autosomal disorder

Answer 43

myotonic dystrophy

Question 44

list chromosomal disorders

Answer 44

Klinefelter’s syndrome- XXY
turner’s syndrome- completely or partially missing X chromosome
down syndrome- condition in which a child is born with an extra copy of their 21st chromosome (not sterile)

Question 45

what is pedigree

Answer 45

it is a family tree in which we observe the passing of a particular trait from 1 generation to another